【作者】 成永生；

【导师】 陈松岭；

【作者基本信息】 中南大学 ， 矿产普查与勘探， 2008， 博士

【摘要】 碳酸盐岩储层由于其强烈的非均质性一直成为石油地质研究的难点,而其中巨大的油气储量却始终吸引着人们不断展开更加深入的探索与研究。南堡凹陷周边凸起地区油气勘探工作始于上世纪60年代,目前勘探与认识程度均较低,而近年来的重大发现却充分展示了其巨大的勘探潜力。因此,本文以南堡凹陷周边凸起地区古生界寒武—奥陶系碳酸盐岩储层为研究对象,以岩石学、沉积学、储层预测、古潜山油气成藏等理论为指导,以野外岩石露头观测与岩心观察相结合的方式,采用偏光薄片、铸体薄片、压汞分析、扫描电镜、X射线衍射、化学全分析、物性分析等方法与技术,结合录井、测井、试油、地震、钻探以及区域地质等成果资料,对寒武—奥陶系碳酸盐岩岩石类型、化学成分、矿物成分、结构构造、沉积特征及沉积环境、储集性能以及储集空间类型、特征、分布及其成因、裂隙发育规律及影响控制因素等进行了深入研究,对碳酸盐岩储层发育影响及控制因素进行了全面分析,开展了碳酸盐岩储层综合评价,深入剖析了古生界潜山油气成藏模式,提出了有利勘探方向。通过薄片鉴定、X射线衍射、化学全分析确定了碳酸盐岩储层的主要岩石类型、矿物成分及结构构造。寒武—奥陶系碳酸盐岩主要岩石类型为灰岩、云质灰岩、泥质灰岩、灰质云岩、泥质云岩和白云岩,矿物成分包括方解石和白云石,以及少量的泥质、黄铁矿、硅质及石膏,具泥、粉晶结构,少量细晶结构。综合评价了寒武—奥陶系碳酸盐岩储层,划分出四种储层类型。Ⅰ类储层为裂缝—溶蚀孔洞型,储集空间结构为细溶孔、大中型洞、小缝型和粗溶孔、大中型洞、中缝型;Ⅱ类储层为洞—缝型,储集空间结构为大中型洞、小缝以及大中型洞、中缝型;Ⅲ类储层为溶孔—裂缝型,储集空间结构为细孔—小缝型和细孔—中缝型:Ⅳ类储层为致密层,储集空间结构为微孔微缝、微裂隙型。依据以上四种储层类型特征,对寒武—奥陶系各组地层分别进行了评价,产生了新的目的层系,为今后勘探提供了方向。对寒武—奥陶系碳酸盐岩储层发育影响因素进行了深入探讨,包括岩石学、成岩作用、构造作用以及古岩溶等,前次提出区内发育有晚期埋藏有机溶蚀作用,其叠加在早期古岩溶作用之上,对储层进行改造,是导致有效储集空间发育、储渗条件改善和储层形成的重要因素。建立了寒武—奥陶系碳酸盐岩古潜山油气成藏模式,总结了油气成藏的主要控制因素及油气分布规律。碳酸盐岩古潜山油气成藏受断层和风化壳联合控制,油气通过断层及风化壳进行联合运移。从层位来看,油气主要分布于府君山组、下马家沟组、馒头组、亮甲山组和毛庄组。从岩性来看,油气主要储集于灰岩和白云质灰岩中。区内主要发育有构造块状油气藏和古潜山不整合油气藏两种油气藏类型,控制油气成藏的关键因素包括岩溶缝洞型储层有效储集体发育程度、油气运移通道、侧向对接、以及储层与生烃凹陷的空间关系等。充分利用碳酸盐岩储层研究成果,结合古潜山油气成藏模式,基于前人已有研究,进行了有利勘探区预测及评价。西南庄—柏各庄凸起是寻找寒武系潜山油藏的有利地区;老王庄—落潮湾凸起是寻找寒武系及奥陶系油藏的有利地区:马头营凸起则是寻找上第三系低幅度批覆构造油藏的有利地区。更多还原

【Abstract】 Because of the serious heterogeneity, carbonate reservoir has been the challenge to the petroleum geology, and the further research is always making just for the great petroleum reserves.The exploration started from 60’s of last century in peripheral of Nanpu sag, but the extent of exploration and knowledge are low at present. However in recent years many important discoveries show the great oil & gas exploration potential. Taking the Paleozoic Cambrian-Ordovician carbonate reservoir in peripheral of Nanpu sag as the study object, based on traditional thin section, cast thin section, mercury intrusion analysis, scanning electron microscope, X-ray diffraction, full chemical analyses, physical analysis, the rock type, chemical constituent, mineral composition, texture and structure, sedimentary characteristics and sedimentary environment, reserving property, reserving space type and its feature, distribution, genesis, law and influence factors to fracture are studied under the guidance of petrology, sedimentology, reservoir prediction, buried-hill accumulation by the means of field investigation and core observation. At the same time the comprehensive analysis of influencing and controlling factors and synthetical evaluation to carbonate reservoir, the study of Paleozoic buried-hill accumulation mode are done, and the potential exploration target are determined.Thin section, X-ray diffraction, full chemical analyses are employed to identification the main rock type, mineral composition, texture and structure. The main rock types of Cambrian-Ordovician carbonate, which is characterized by mud-crystal structure or powder-crystal structure, fine crystalline structure for a little, are composed of limestone, dolomitic limestone, argillaceous limestone, calcareous dolomite, argillaceous dolomite, dolomite. The main mineral compositions are: calcite, dolomite, and little of argillaceous, pyrite, siliceous and gypsum.Cambrian-Ordovician carbonate reservoir is evaluated synthetically. And the result shows that it can be classified into four types. The first class is fracture-corrosion pore reservoir, which reservoir space includes fine dissolved pore, large-medium size hole, small fracture or big dissolved pore, large-medium size hole, medium-size fracture. The second class is cavity-fracture reservoir, which reservoir space includes large-medium size hole, small fracture, or large-medium size hole, medium size fracture. The third class is dissolved pore and fracture reservoir, which reservoir space includes fine pore, small fracture or fine pore, medium size fracture. The forth class is compact reservoir, which reservoir space consists of micro-pore, micro-crack, and micro-fissure. According to the above reservoir class, each formation of Cambrian-Ordovician reservoir is evaluated, and the new favorable formations are put forward, it provides a direction for the future exploration.It discusses the influence factor to Cambrian-Ordovician carbonate reservoir, such as petrology, diagenesis, tectonic, paleokarst, etc. And it is put forward firstly that there exists the late burial organic dissolution, which overprints the early paleokarst, improves the reservoir, and is one of the important factors to improve store-permeability conditions and reservoir formation.It establishes the hydrocarbon accumulation mode of Cambrian-Ordovician carbonate ancient buried-hill, summarizes the key control factors of hydrocarbon accumulation and oil & gas distributing rule. Ancient buried-hill accumulation is mainly controlled by fault and weathering crust, which are also the hydrocarbon migration pathway. From the view of stratum, oil & gas is distributed mainly in the formation of Fujunshan, Xiamajiagou, Mantou, Liangjiashan, Maozhuang. From the view of lithology, oil & gas is distributed mainly in limestone and dolomitic limestone. There exist two types of hydrocarbon reservoir, including structural-massive hydrocarbon reservoir and buried-hill unconformity hydrocarbon reservoir. The key factors, which control the accumulation, consist of valid reservoir, migration pathway, lateral joint, and the spatial relationship between reservoir and hydrocarbon generation sag.Based on the research results of carbonate reservoir and previous research, combine the accumulation mode of buried-hill, the prospective sites are put forwarded and evaluated. In Xinanzhuang-baigezhuang uplift, Cambrian buried-hill reservoir is the potential target. In Laowangzhuang-luochaowan uplift, Cambrian-Ordovician reservoir is the exploration object. Upper tertiary low amplitude tectonic reservoir is the favorable exploration direction in the area of Matouying uplift.更多还原